IP Library › Granted Patent US 4,718,679
Granted Patent Utility
US 4,718,679 · App. 07/003,679

Lockdown ring assembly for wellhead seal

Inventor: Larry A. Vyvial
Patented Case View Patent ↗
Granted: Jan 12, 1988 Filed: Jan 15, 1987
Inventor
Larry A. Vyvial
Assignee (at issue)
Cooper Industries Holdings

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Quick Facts
Patent No.
US 4,718,679
App. No.
07/003,679
Filed
1987-01-15
Granted
1988-01-12
Kind
A